The invention relates to a closure system for a leakproof baby feeding bottle.
In known baby feeding bottles, the teat at the lower edge has a peripheral teat flange which is secured sealingly to the edge of a bottle opening by means of a screw ring screwed onto an external thread of the bottle. In order to prevent leakage of liquid during breaks from drinking, a lid is placed between the teat flange and the flange edge and secured by means of the screw ring.
A more user-friendly leakproof baby feeding bottle is disclosed in DE 101 57 071 C1. Said bottle has a lower closure ring which is screwed onto the external thread of the bottle and which has a first seat surface with at least one first throughflow hole.
An upper closure ring has a second seat surface with at least one second throughflow hole. The two closure rings are able to be rotated relative to one another and releasably locked together via locking elements. By rotating the upper closure ring, the first and second throughflow holes are able to be brought into overlapping and non-overlapping positions. A drinking teat is screwed by means of a screw ring to an external thread of the upper closure ring. If the throughflow holes overlap one another, baby food is able to be taken through the drinking teat. If the throughflow holes do not overlap one another, the removal of baby food through the drinking teat is blocked.
In the exemplary embodiment, the closure rings comprise conical seat surfaces. Moreover, sealing rings are present on the lower face of the lower closure ring and on the upper face of the first seat surface. The lower closure ring comprises a locking projection protruding inwardly from the lower conical seat surface and the upper closure ring has snap tongues protruding from the lower second conical seat surface and which engage behind the locking projection.
The manufacture and usage of the leakproof bottle is, to a certain extent, still complicated. Due to the complex spatial shape, dirt is able to collect on the closure rings. The snap tongues come into contact with the baby food and have to be handled for dismantling. The cleaning of the closure rings is complicated.
WO 2007/042117 A1 discloses a leakproof baby feeding bottle which simplifies the manufacture and usage. One variant comprises a closure system with a lower closure ring, which has a substantially cylindrical first peripheral part with a first internal thread which is screwed onto an external thread of a bottle, and which comprises a first central part connected to the upper edge of the first peripheral part, with a first seat surface rotationally symmetrical about a longitudinal axis and facing away from the bottle interior, at least one first throughflow hole which opens, on the one hand, in the first seat surface and, on the other hand, in one side of the first central part facing the bottle interior and a soft elastic sealing material made of plastics material, injection-moulded onto the first seat surface at least around the edge of the throughflow hole and onto a sealing surface of the first central part sealingly positioned on the upper bottle edge and which extends from the first seat surface through the first throughflow hole along the side facing the bottle interior as far as the sealing surface of the first central part. Moreover, the closure system comprises an upper closure ring which has a substantially cylindrical second peripheral part with a second external thread, on which a drinking teat of a screw ring with an internal thread is fixed and which comprises a second central part connected to the second peripheral part, with a second seat surface rotationally symmetrical about the longitudinal axis and sealingly located on the first seat surface, and at least one second throughflow hole which opens, on the one hand, in the second seat surface and, on the other hand, in one side of the second central part remote therefrom, and which by rotating the upper closure ring relative to the lower closure ring may be brought into overlapping and non-overlapping positions relative to the first throughflow hole. Moreover, locking elements are present which rotatably and releasably connect together the lower closure ring and the upper closure ring relative to one another.
According to the exemplary embodiment, the soft elastic sealing material is injection-moulded on the lower closure ring and covers a circular portion surrounding the throughflow holes on the first seat surface. Moreover, on the inner periphery of the throughflow holes in each case the sealing material has a strip-shaped portion. On the lower face of the first central part, coming from the strip-shaped portions, further strip-shaped portions of the soft elastic sealing material are present, which extend down the inner face of a cylindrical portion of the first peripheral part and are connected at the bottom to an annular peripheral sealing surface made of the same material, which is arranged on the inner face of a step of the first peripheral part. The sealing material is, for example, a thermoplastic elastomer.
In the known closure system, the seal is created between the lower closure ring and the upper closure ring between the circular disc-shaped soft elastic sealing material of the first seat surface of the lower closure ring and the substantially planar second seat surface of the upper closure ring, located thereon. Here, it may lead to leakages, in particular when the seat surfaces do not bear exactly against one another with a specific contact pressure. Moreover, the friction between the first seat surface made of soft elastic sealing material and the second seat surface, may hinder the rotation of the upper closure ring relative to the lower closure ring.
Against this background, the object of the invention is to provide a closure system for a leakproof baby feeding bottle with improved usage properties.